Breathing is so automatic that we almost never think about it. Yet a very simple variable can reveal a great deal about our physiological state: respiratory rate.
Respiratory rate refers to the number of breaths a person takes per minute. Each breath includes an inhalation and an exhalation. Along with heart rate, blood pressure, temperature, and oxygen saturation, it is one of the main vital signs used in medicine to assess the body’s condition [1].
For decades, it has been one of the least monitored vital signs outside clinical settings. That is beginning to change.
How respiratory rate is measured
Traditionally, respiratory rate is measured simply by counting breaths over a specific period of time. In clinical settings, a healthcare professional typically observes chest movements for 30 or 60 seconds.
The method works, but it has clear limitations. It requires constant attention, counting errors are common, and it only provides a brief snapshot of breathing.
Modern technologies now allow respiration to be measured continuously. Sensors that detect chest movement or changes in airflow can estimate respiratory rate in real time, opening new possibilities for understanding human physiology.
Normal values
In healthy adults at rest, respiratory rate typically ranges between 12 and 20 breaths per minute, with population averages around 14 to 16 breaths per minute [2].
Population-based studies have shown that this value tends to remain relatively stable throughout adulthood. However, it may increase slightly with age or in the presence of certain health conditions. Higher resting respiratory rates have been associated with obesity, smoking, and cardiopulmonary diseases, reflecting how breathing quickly responds to changes in metabolic or cardiovascular status [2].
How Respiratory Rate Responds to Exercise
During exercise, ventilation increases to meet the body’s higher metabolic demands. Active muscles consume more oxygen and produce more carbon dioxide, so the respiratory system must rapidly adapt to maintain physiological balance.
In the early stages of exercise, the increase in ventilation occurs primarily through an increase in tidal volume, meaning deeper breaths that move a greater amount of air with each breathing cycle.
As exercise intensity rises, this mechanism alone is no longer sufficient. At this point, respiratory rate begins to increase more noticeably, allowing total ventilation to continue rising.
During incremental exercise tests, respiratory rate typically increases progressively and shows more pronounced changes around the ventilatory thresholds, making it an interesting marker of the physiological intensity of effort [3].
| Situation | Respiratory rate |
| Resting adults | 12–20 breaths/min |
| Moderate exercise | 25–40 breaths/min |
| High intensity exercise | 40–60+ breaths/min |
Respiratory rate and health
Respiratory rate is one of the most sensitive indicators of physiological stress.
In medicine, it is considered an early signal of clinical deterioration. An increase in respiratory rate can occur during infections, cardiovascular problems, metabolic disturbances, or respiratory diseases. In fact, several clinical early warning systems use respiratory rate as one of their key indicators [4].
In the context of training, it can also provide useful information. Unexpected changes in breathing during familiar workloads may reflect accumulated fatigue, illness, or overtraining processes, since ventilation responds quickly to changes in metabolic and autonomic balance [3].
Why measuring it in real time changes the game
Until recently, respiratory rate was difficult to measure outside laboratories or clinical environments. Most of the available data came from occasional observations or laboratory exercise tests.
New technologies are changing this scenario.
With devices such as Chaski, it is now possible to monitor respiratory rate in real time during training sessions and everyday activities. This makes it possible to observe how breathing responds to changes in intensity, fatigue, heat, stress, or recovery.
For coaches and endurance athletes, this opens a direct window into physiological processes that previously could only be evaluated in the laboratory.
And for non-athletes, it provides a simple and accessible way to better understand how the body responds to both physical and mental stress.
Sometimes the most powerful signals from the body are also the most basic ones.
Breathing is one of them.
Sources
[1] Benchetrit, G. (2000). Breathing pattern in humans: Diversity and individuality. Respiratory Physiology, 122(2–3), 123–129. https://doi.org/10.1016/S0034-5687(00)00154-8
[2] Meyer, M., Peters, A., Schulz, H., et al. (2024). Resting respiratory rate in a population-based cohort and its association with demographic, lifestyle, and health factors. PLoS ONE, 19(2), e0318502. https://doi.org/10.1371/journal.pone.0318502
[3] Nicolò, A., Massaroni, C., & Schena, E. (2017). Respiratory frequency as a marker of exercise intensity. Sports Medicine, 47(6), 1033–1045. https://doi.org/10.1007/s40279-016-0651-4
[4] Subbe, C. P., Kruger, M., Rutherford, P., & Gemmel, L. (2001). Validation of a modified Early Warning Score in medical admissions. QJM: An International Journal of Medicine, 94(10), 521–526. https://doi.org/10.1093/qjmed/94.10.521